3 ms·
Lightning Strike Energy == 1,000,000,000 Joules 1 Joule heats 1g water 0.24 C 1 L water == 100g 1 cu.meter water = 1000L Room Temp == 23 C Thus: (77/0.24)
by heimdall 8y ago
Lightning Strike Energy == 1,000,000,000 Joules
1 Joule heats 1g water 0.24 C
1 L water == 100g
1 cu.meter water = 1000L
Room Temp == 23 C
Thus:
(77/0.24) = 320.8 Joules raises 1g water from 23 C to 100 C (boiling).
(1E9 Joules / 320.8 Joules) lightning strike with no losses along the way heats 3,116,883g of water.
3,116,883g of water == 31,168 L of water == 31 cu.meters of water. This is a block of water 1m x 3m x 10m.
Steam volume is 1600x liquid water volume. So even if we say that 90% of the energy is lost in the transfer, that's still 3 cubic meters of water that flash-boils into steam, quite possibly causing damage to the bridge.
So: perhaps unlikely, but quite possible.
Edit: 3,116,883g of water == 3,117 L of water == 3 cu.meters of water. Damn math errors, always creeping in. Still unlikely, still possible.
- jakewins 8y agoIndeed. Lightning does this to trees all the time, there's a lot of crazy videos on YouTube of lightning causing trees to explode. https://en.wikipedia.org/wiki/Exploding_tree#Lightning https://en.wikipedia.org/wiki/Exploding_tree#Lightning
- astrodust 8y agoTrees have relatively high resistance so they absorb a lot of energy. The lower the resistance, the lower the impact.
- silvestrov 8y ago3,116,883g water is 3,117 liters and not 31,168 liters: http://m.wolframalpha.com/input/?i=3%2C116%2C883g+water+in+liter http://m.wolframalpha.com/input/?i=3%2C116%2C883g+water+in+l...
- UnFleshedOne 8y ago1L of water is 1000g, then you need additional 2261 joules per gram to evaporate. So 1E9j will evaporate 384 liters of water, so 0.384 cubic meters (unless I lost a degree of magnitude here or there myself :)).
- heimdall 8y agohttps://www.smbc-comics.com/comics/20130616.png https://www.smbc-comics.com/comics/20130616.png
- vlehto 8y agoYes but the steel cable ought to conduct the electricity through the water column into the structure. If there is sufficient resistor in the structure for massive steam explosion, then it's very unlikely that the lightning would ever strike there.